JPH0760877B2 - Power semiconductor device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a power semiconductor device such as a power module in which a connection end of an electrode terminal held in an outer case is exposed to the outside.

[Conventional technology]

4 and 5 are a plan view and a side sectional view of a power semiconductor device including a power module using a general outer case, and FIG. 4 is shown without a filling resin. In addition,
Although there are a total of seven electrode terminals in the figure, holding the electrode terminals 1 of the main circuit will be described below. Reference numeral 2 is a copper base plate made of metal or the like, and an insulating metallized substrate 3 is fixed to the upper surface thereof. Reference numeral 4 denotes an outer case made of a synthetic resin molded product, which holds each electrode terminal 1 in the holding groove 5a of the electrode holding portion 5 in the upright direction so that the connecting end is projected upward, and the copper base plate 2 is provided at the lower end. It is glued. The outer case 4 is filled with a synthetic resin material 6 made of silicon gel or the like in the lower half portion and a synthetic resin material 7 made of an epoxy resin or the like in the upper half portion.

The above semiconductor device is assembled as follows. First, the insulating metallized substrate 3 is fixed on the copper base plate 2 by soldering or the like, and various semiconductor chips (not shown) are fixed on the insulating metallized substrate 3 by soldering or the like. An adhesive is applied to the surface of the copper base plate 2 that is bonded to the outer case, and a solder material is applied to the upper surface of the insulating metallized substrate 3 that is to be bonded to the electrode terminals 1.

On the other hand, the electrode terminal 1 is inserted from above and held in the holding groove 5a of the electrode holding portion 5 of the outer case 4. The outer case 4 in this state is shown in FIG.

The outer case 4 in the assembled state shown in FIG. 6 is placed on the copper base plate 2 in the assembled state and heated to bond the outer case 4 to the copper base plate 2 and the electrode terminals 1 on the insulating metallized substrate 3. To join.

Arrangement pattern (not shown) on the insulating metallized substrate 3
Is formed, and the electrode terminal 1 is soldered on the lower end surface on this wiring pattern. This solder joint is
It is a very important part in a power module that carries a large current, and attention is paid to making a good solder joint state. A good solder joint condition is electrode terminal 1
Is that the lower end surface of the solder is bonded at a predetermined position of the wiring pattern on the insulating metallized substrate 3 with the solder having a predetermined thickness without variation.

As described above, when the outer case 4 is bonded to the copper base plate 2 part, the lower half part is filled with the synthetic resin material 6 and the upper half part is filled with the synthetic resin material 7 in the outer case 4. And cure.

Next, a means for holding the electrode terminal 1 of the outer case 4 will be described. FIG. 7 shows the electrode terminal 1 of FIG. Supporting projections 1a are provided on both sides of the intermediate portion of the electrode terminal 1, a projecting projection piece 1b is exposed in the thickness direction, a lower bifurcated portion 1c is bent in a Z shape, and a lower end surface is formed horizontally. ing. This electrode terminal 1
Each supporting protrusion 1a is inserted into the holding groove 5a of each electrode holding portion 5 from above, and is held by elastic pressing of the protruding piece 1b.

However, as shown in FIGS. 8 and 9, the electrode terminal 1 is not kept vertical and tends to tilt. This is for facilitating the insertion work of the electrode terminal 1 into the holding groove 5a of the electrode holding portion 5 and for preventing damage or the like during insertion.
Width d of the holding groove 5a (with respect to the thickness direction of the holding portion 5)
Is larger than the thickness t of the electrode terminal 1 (supporting protrusion 1a) by b to allow a space.

Therefore, as shown in FIG. 8, when the projecting protrusion 1b is located above the groove 5a, the protrusion 1a elastically presses,
With this portion as a fulcrum, the electrode terminal 1 is held at an angle of e °.

Further, as shown in FIG. 9, when the protruding piece 1b is located below the groove 5a, the electrode terminal 1 is held at an angle e ° with this portion as a fulcrum.

Therefore, the lower end surface of the electrode terminal 1 forms a gap with the upper surface of the insulating metallized substrate 3, resulting in poor soldering. In addition, a position shift in the horizontal direction with respect to the wiring pattern occurs in proportion to the distance f to the insulating metallized substrate 3.

[Problems to be Solved by the Invention]

In the conventional power semiconductor device as described above, the electrode terminal 1
Although the projecting protrusion 1b is provided on the supporting protrusion 1a, the electrode terminal 1 may be inclined with the protrusion 1b as a fulcrum within the holding groove 5a of the electrode holder 5, and the lower end surface of the electrode terminal 1 may be inclined. However, there is a problem in that the solder is inclined with respect to the corresponding solder joint surface, the solder thickness is not uniform, the soldering becomes defective, and the corresponding solder joint surface is displaced.

The present invention has been made to solve such a problem, when the outer case is joined to the metal base plate, the electrode terminals are held vertically to the electrode holding portion of the outer case,
An object of the present invention is to obtain a power semiconductor device in which the lower end surface is in uniform contact with the corresponding connection substrate surface, has no horizontal positional displacement, and is well soldered.

[Means for Solving the Problems]

In the power semiconductor device according to the present invention, in the invention according to claim 1, the holding groove of the electrode holding portion of the outer case is provided on both sides of the supporting protrusions on both sides of the electrode terminal, and on the inner surface on the side of the projecting protrusion. There is a gap in the direction of the protruding piece and there is a step that eliminates the gap in the part far from the protruding piece.On the inner surface to the opposite side of the protruding piece, the height position part of the protruding piece eliminates the gap and is far from the protruding piece. A step having a gap is provided on one side.

According to the second aspect of the invention, the embossed protrusions provided on the support protrusions on both sides of the electrode terminal are located at the center position in the depth direction of the holding groove of the electrode holding portion of the outer case.

[Action]

According to the invention of claim 1, when the electrode terminal is inserted into the holding groove of the electrode holding portion of the outer case by the supporting protrusion, the pushing protrusion is elastically pressed to oppose the protrusion of the supporting protrusion. The side surface is pressed against the inner surface of the corresponding groove without a gap, and the side surface of the protruding piece of the support protrusion is in contact with the inner surface of the corresponding holding groove without a gap. As a result, the electrode terminal is held vertically by the stepped holding groove without tilting, and the lower end surface contacts the corresponding joint surface of the connecting body without tilting, and good soldering is performed.

Further, in the invention of claim 2, the electrode terminal is supported by the protruding portion,
When inserted into the holding groove of the electrode holding portion of the outer case, the projecting projection piece of the supporting protrusion elastically presses the supporting protrusion against the inner surface of the corresponding groove at the center position in the depth direction of the holding groove. As a result, the electrode terminal is vertically held by the holding groove of the electrode holding portion without tilting, and the lower end surface is in contact with the joining surface of the corresponding connector without tilting, and good soldering is performed.

〔Example〕

FIG. 1 shows an electrode terminal holding means of a power semiconductor device according to an embodiment of the present invention. In the figure, the embossing protrusions 1b provided on the support protrusions 1a on both sides of the electrode terminal 1 are located below the groove 5a of the electrode holding portion 5 of the outer case 4. t indicates the thickness of the electrode terminal 1.

The inner surface of the holding groove 5a with respect to both sides of the supporting protrusion 1a is a protrusion piece.
The surface on the 1b side has a gap b at the position of the protruding piece 1b, and a step away from the protruding piece 1b is provided with a step, and the surface on the opposite side of the protruding piece 1b is located at the position of the protruding piece 1b. There is no gap in the area, and there is a step with a gap c on the side farther from the protruding piece 1b. Due to the gaps b and c of the holding groove 5a, the supporting protrusion 1a of the electrode terminal 1 is easily inserted into the holding groove 5a from above. The lower side of the supporting protrusion 1a is pressed against the corresponding inner surface of the groove 5a by the elastic pressing of the protruding piece 1b, and the upper side of the groove 5a is pressed.
It is received by the reaction force P on the corresponding inner surface.

In this way, the electrode terminal 1 has the supporting protrusions 1a with the electrode holding portions 5a.
It is held vertically by being inserted into the holding groove 5a having a stepped inner surface, and the lower end surface is evenly soldered without being inclined to the surface of the insulating metallized substrate 3.

FIG. 2 shows another embodiment of the present invention, in which the position of the protruding piece 1b of the supporting protruding portion 1a of the electrode terminal 1 is above the holding groove 5a. Therefore, the inner surface of the holding groove 5a corresponding to both surfaces of the support protrusion 1a has a gap b at the position of the protrusion piece 1b and a gap away from the protrusion piece 1b on the surface facing the protrusion piece 1b. A step is provided, and the surface opposite to the protruding piece 1b is provided with a step in which a portion close to the position of the protruding piece 1b has no gap and a portion far from the protruding piece 1b has a gap c.

In this way, the supporting protrusion 1a is pressed against the corresponding inner surface of the holding groove 5a by the elastic pressing of the protruding piece 1b, and the lower side is received by the corresponding inner surface of the groove 5a by the reaction force P and is held vertically without inclination. It

The positions A and B of the step on the inner surface of the holding groove 5a are set at the support protrusion 1
a does not hinder the insertion into the holding groove 5a, and the electrode terminal 1
Are not limited to the positions shown in FIGS. 1 and 2 as long as they are held vertically.

Next, FIG. 3 is a partially sectional side view showing an electrode terminal holding means of a power semiconductor device according to another different embodiment of the present invention. In the figure, the inner surface of the holding groove 5a of the electrode holding portion 5 of the outer case 4 is the thickness of the electrode terminal 1 (supporting protrusion portion).
The same as the thickness of 1a) and a width d with a gap b for t,
Both supporting protrusions 1a are easily inserted into the groove 5a. The position of the projecting protrusion 1b of the support protrusion 1a in the height direction is set to the center position of the depth of the groove 5a. This position is, for example, a ± 1 mm.

When the electrode terminal 1 is inserted into the groove 5a with both the supporting protrusions 1a, the protruding piece 1b bites into the inner surface of the groove 5a and elastically presses at the central position in the depth direction, and the supporting protrusion 1a is pressed against the inner surface on the opposite side. There is. In this way, the electrode terminal 1 inserted in the groove 5a is held vertically without tilting, and the lower end surface is insulated by the insulating metallized substrate 3
The surface is in contact without tilting, and good soldering is achieved.

〔The invention's effect〕

As described above, according to the present invention, in the invention of claim 1, the inner surface in the width direction of the holding groove of the electrode holding portion of the outer case is provided on the surface on the side with respect to the projecting projection piece at the projection piece position. A step with a gap is provided in the part far from the projection piece, and a step with no gap is provided on the opposite side of the projection piece at the position where the projection piece is located and a gap is provided farther from the projection piece. Therefore, the supporting protrusion is easily inserted into the groove, and the electrode terminal is held in the electrode holding portion without tilting,
The lower end surface of the electrode terminal is not inclined to the joint surface of the connection body, good solder connection is made, and the positional displacement in the horizontal direction is eliminated.

In the invention of claim 2, the width of the holding groove of the electrode holding portion of the outer case has a gap with respect to the thickness of the supporting protrusion of the electrode terminal, and the position of the protruding protrusion of the supporting protrusion is Since the holding groove is located at the center position of the depth, the same effect as the invention of claim 1 can be obtained.

[Brief description of drawings]

FIGS. 1, 2 and 3 are partially sectional side views showing the electrode terminal holding means of the power semiconductor device according to the first, second and third embodiments of the present invention, and FIG. 4 is a general view. FIG. 5 is a plan view showing the power semiconductor device in the case of a typical power module, excluding the filled synthetic resin material, FIG. 5 is a side sectional view of the device of FIG. 4 in a state filled with the synthetic resin material, and FIG. 5 is a side sectional view of the outer case of FIG. 5 with the electrode terminals held, FIGS. 7 (a) and 7 (b) are front and side views of the electrode terminals of FIG. 6, FIG. 8 and FIG. FIG. 4 is a partially sectional side view showing each example of an electrode terminal holding means of a conventional power semiconductor device. 1 ... Electrode terminal, 1a ... Support protrusion, 1b ... Embossed protrusion piece, 3 ... Connection board (insulating metallized board), 4 ... Outer case, 5 ... Electrode holder, 5a ... Holding groove The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (2)

[Claims] 1. An electrode terminal having punched-out projections extending in the thickness direction on both sides of an intermediate portion in the height direction, a lower portion bent and a lower end surface formed horizontally, and a synthetic resin molded product. Becomes
An outer case for inserting the electrode terminals on both sides of the intermediate part and holding it in a vertical direction in a holding groove formed in an electrode holding part provided inside, and an outer case arranged at a lower end portion of the outer case, and being provided on the upper surface with the above The lower end surface of the electrode terminal is provided with a connection substrate to be soldered, and the width direction inner surface of the holding groove of the electrode holding portion is a surface with respect to the protrusion piece side, and the protrusion piece position is a gap from both sides of the intermediate portion. A gap that eliminates the gap on both sides of the intermediate part at the part far from the projection piece, and on the surface opposite to the projection piece, place the height position part where the projection piece is located on both sides of the intermediate part. A power semiconductor device, in which the electrode terminal is held perpendicularly by providing a step away from the projecting piece on both sides of the intermediate portion. 2. An electrode terminal in which punched-out projection pieces are projected in the thickness direction on both sides of an intermediate portion in the height direction, a lower portion is bent and a lower end surface is horizontally formed, and a synthetic resin molded product. And an outer case in which the electrode terminals are inserted and held in the vertical direction on both sides of the intermediate part in a holding groove formed in the electrode holding part provided inside, and the outer case is arranged at the lower end of the outer case. In the connection substrate to which the lower end surface of the electrode terminal is soldered, the width of the holding groove of the electrode holding portion has a gap with respect to the thickness of both sides of the intermediate portion, A power semiconductor device in which the position in the height direction is at the center of the depth of the holding groove, and the electrode terminals are held vertically.